1. Field of the Invention
The present invention relates to a lubricator adapted to atomize lubricating oil into an air stream supplied to air-actuated devices such as an air cylinder or an air motor.
2. Description of the Prior Art
The lubricator commonly used is typically so constructed that a cover provided with a substantially horizontal air conduit including an orifice extending therethrough is received on the upper side of an oil cup, said cover is formed in its upper side with a supply hole extending to said orifice, a transparent oil drop cylinder having a drop hole through its top side is mounted on said cover so as to overlay said supply hole, a quantity of oil contained within the oil cup pulled upwards to a space above the oil drop cylinder under a suction effect of a pressure differential between within the oil cup and within the orifice is dropped through the drop hole into the oil drop cylinder and then atomized through the supply hole into the air stream flowing through the orifice. Means for adjusting a quantity of oil drop in the above-mentioned lubricator of prior art is, as disclosed in the specification of U.S. Pat. No. 3,707,204, so arranged that an outer cylinder communicatiing with a syphon tube adapted to pump up oil is fitted on the upper end of the oil drop cylinder, an adjustment screw provided on its lower end with a needle valve in alignment with the drop hole is threaded on cap means put on the upper side of said outer cylinder, an aperture of the drop hole is adjusted by rotating the adjustment screw and thereby a quantity of oil drop is adjusted. In such construction, upward projection of the adjustment screw results in increasing an overall height of the structure, which requires, in turn, a relatively large space for mounting, increased number of parts and disadvantageously increased manufacturing cost.